Data center cooling system

ABSTRACT

A modular data center includes a plurality of racks, each of the racks having a front face and a back face, wherein the plurality of racks is arranged in a first row and a second row, such that the back faces of racks of the first row are facing the second row, and the back faces of the racks of the second row are facing the first row, a first end panel coupled between a first rack of the first row and a first rack of the second row, the first end panel having a bottom edge and a tope edge, a second end panel coupled between a second rack of the first row and a second rack of the second row, the second end panel having a top edge and a bottom edge, and a roof panel coupled between the top edge of the first panel and the top edge of the second panel.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application under 37 CFR §1.53(b) ofU.S. Ser. No. 10/391,971, (U.S. Pat. No. 6,859,366), filed on Mar. 19,2003, and entitled, “Data Center Cooling System,” which is assigned tothe assignee of this application and is herein incorporated by referencein its entirety.

FIELD OF THE INVENTION

Embodiments of the present invention are directed to cooling ofrack-mounted devices, and more particularly to a data centerinfrastructure having a cooling system.

BACKGROUND OF THE INVENTION

Electronic equipment racks generally are designed to receive a number ofelectronic components arranged vertically in the rack, mounted onshelves, and/or to front and rear mounting rails. The electronicequipment may include, for example, printed circuit boards,communications equipment, computers, including computer servers, orother electronic components.

Electronic equipment housed in racks produces a considerable amount ofheat, which undesirably affects performance and reliability of theelectronic equipment. Often the heat produced by the rack-mountedcomponents is not evenly distributed in the racks. Temperature gradientscausing elevated inlet temperatures at tops of racks, for example,reduce equipment reliability substantially. Equipment reliability may bereduced by as much as half the reliability of specific equipmentfunction for each 10° F. rise in temperature. Accordingly, rack-mountedcomputer systems typically require effective cooling systems to maintainoperational efficiency. Cooling can be accomplished by introducingcooled air into an equipment rack causing the air to flow throughequipment in the rack and exit the rack at an increased temperature,thereby removing some of the heat. The heat removed from the rack istypically returned into the room containing the racks and the entireroom is cooled using a relatively large air conditioning system.

SUMMARY OF THE INVENTION

A first aspect of the present invention is directed to a modular datacenter. The modular data center includes a plurality of racks, each ofthe racks having a front face and a back face, wherein the plurality ofracks is arranged in a first row and a second row, such that the backfaces of racks of the first row are facing the second row, and the backfaces of the racks of the second row are facing the first row. The datacenter also includes a first end panel coupled between a first rack ofthe first row and a first rack of the second row, the first end panelhaving a bottom edge and a tope edge. Further, the data center includesa second end panel coupled between a second rack of the first row and asecond rack of the second row, the second end panel having a top edgeand a bottom edge, and a roof panel is included to couple between thetop edge of the first panel and the top edge of the second panel.

The modular data center can be designed so that the roof panel iscoupled to a top portion of at least one rack of the first row and to atop portion of at least one rack of the second row, such that the roofpanel, the first end panel, the second end panel, and the first andsecond rows of racks form an enclosure around an area between the firstrow of racks and the second row of racks. The plurality of racks canfurther include cooling equipment that draws air from the area, coolsthe air and returns cooled air out of the front face of one of theracks. At least one of the first end panel and the second end panel caninclude a door. Further, at least a portion of the roof panel can betranslucent. The modular data center can have at least one rack thatincludes an uninterruptible power supply to provide uninterrupted powerto equipment in at least one other rack of the plurality of racks. Thefirst row of racks in the modular data center can be substantiallyparallel to the second row. In addition, the modular data center can bedesigned such that one of the plurality of racks includes coolingequipment that draws air from an area between the first row and thesecond row, cools the air and returns cooled air out of the front faceof one of the racks.

Another aspect of the present invention is directed to a method ofcooling electronic equipment contained in racks in a data center. Themethod includes arranging the racks in two rows, including a first rowand a second row that is substantially parallel to the first row, with aback face of at least one of the racks of the first row facing towards aback face of at least one of the racks of the second row. The methodalso includes forming an enclosure around an area between the first rowand the second row, and drawing air from the area into one of the racksand passing the air out of a front face of the one of the racks.

The method can include a further step of cooling the air drawn into theone of the racks prior to passing the air out of the front face. Thestep of forming an enclosure may include coupling first and second sidepanels and a roof panel between the first row and the second row. Atleast one of the first side panel and the second side panel may includea door and the roof panel can include a translucent portion.Additionally, the method can include using an uninterruptible powersupply to provide power to equipment in the racks.

Yet another aspect of the present invention is directed to a modulardata center that includes a plurality of racks, each of the racks havinga front face and a back face, wherein the plurality of racks is arrangedin a first row and a second row, such that the back faces of the racksof the first row are facing the second row, and the back faces of theracks of the second row are facing the first row. The modular datacenter further includes means for enclosing a first area between thefirst row and the second row, and means for drawing air from theenclosed area, cooling the air, and returning cooled air to a secondarea.

The means for drawing air can further include means for passing cooledair through the front face of one of the racks. The modular data centercan also be comprised of means for providing uninterruptible power toequipment in the racks. Access means for allowing access into the firstarea may also be a design feature of the modular data center.

The invention will be more fully understood after a review of thefollowing figures, detailed description and claims.

BRIEF DESCRIPTION OF THE FIGURES

For a better understanding of the present invention, reference is madeto the figures which are incorporated herein by reference and in which:

FIG. 1 is a perspective view of a modular data center cooling system forrack-mounted equipment in accordance with one embodiment of theinvention;

FIG. 2 is a top view of another modular data system, similar to thesystem of FIG. 1; and

FIG. 3 is a block flow diagram of a process of cooling equipment mountedin modular data centers in one embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the invention provide a data center infrastructure havinga cooling system for cooling rack-mounted electronic equipment.Embodiments of the invention provide a modular data center forrack-mounted equipment, wherein the modular data center provides powerdistribution, cooling and structural support for the rack-mountedequipment. The power distribution unit and cooling is provided in someembodiments using redundant systems to prevent downtime due toelectrical or mechanical failures. As understood by those skilled in theart, other embodiments are within the scope of the invention, such asembodiments used to provide infrastructure for equipment other thanelectronic equipment.

A system for providing power distribution for rack-mounted equipmentwhich can be used with embodiments of the present invention is describedin U.S. patent application Ser. No. 10/038,106, entitled, “AdjustableScalable Rack Power System and Method,” which is herein incorporated byreference.

Referring to FIG. 1, a perspective view of a modular data center 10 isshown. The modular data center 10 includes a power distribution unit 14,a power protection unit 12, a floor mounted cooling unit 16, equipmentracks 18, and a hot room 22. The modular data center 10 also has a door52 having a window 54, a roof 56, a cold water supply and return 60, anda voltage feed 58. The data center 10 is a modular unit comprised of thepower distribution unit 14, the power protection unit 12 the floormounted cooling unit 16, and equipment racks 18 positioned adjacent toeach other to form a row 32 and a row 34. Row 32 and row 34 aresubstantially parallel. The power distribution unit 14 and the powerprotection unit 12 can be located directly adjacent to one another, andcan be located at the end of one of the rows. The floor-mounted coolingunit 16 may be located and positioned adjacent to the power distributionunit 14. Remaining enclosures forming the at least one additional row inthe data center 10 are equipment racks 18. The hot room 22 is locatedbetween row 32 and row 34, and rows 32 and 34 comprise two of theperimeter walls of the modular data center 10.

The power distribution unit 14 typically contains a transformer, andpower distribution circuitry, such as circuit breakers, for distributingpower to each of the racks in the modular data center 10. The powerdistribution unit 14 provides redundant power to the racks 18 and canmonitor the total current draw. An uninterruptible power supply canprovide uninterruptible power to the power distribution unit 14.Preferably, the power distribution unit 14 includes a 40 kWuninterruptible power supply having N+1 redundancy, where the ability toadd another power module provides N+1 redundancy. In one embodiment ofthe invention, input power to the power distribution unit 14 is receivedthrough the top of the rack from a voltage feed 58. In one embodiment,the voltage feed 58 is a 240 volt feed coupled to the power distributionunit 14 that enters through the roof panel 56. Alternatively, the inputpower may be received from underneath the rack, as through a raisedfloor, or through the back of the rack.

The power protection unit 12 provides redundant power protection forcentralized information technology equipment, as is contained in theequipment racks 18. The power protection unit 12 can have individualpower modules and battery modules that can be individually added orremoved to accommodate different load requirements. The use of multiplepower modules and battery modules provides redundancy by allowingcontinued operation despite the failure of any one power module orbattery module. For example, the power protection unit can include aSymmetra PX® scalable, uninterruptible power supply having a three-phaseinput and a three-phase output, available from American Power ConversionCorporation, of West Kingston, R.I., or the power protection unit caninclude one of the uninterruptible power supplies described in U.S. Pat.No. 5,982,652, titled, “Method and Apparatus for ProvidingUninterruptible Power,” which is incorporated herein by reference.

The floor mounted cooling unit 16 provides heat removal by use of achilled water supply, which enters the unit through supply line 60.Alternatively, the cooling units can provide heat removal using DXcompressorized cooling via use of a direct expansion refrigerant-basedunit, which can be in the unit itself. The cooling unit contains aprimary chilled water coil and secondary direct expansion coil withinthe same frame. The cooling unit can be configured for air, water orglycol use. Cooled air can be released through the bottom of the unit orthe top of the unit. In one embodiment of the invention, cool air isreleased from the cooling unit 16 out its front face, so that the airflow is from the back of the rack and out the front of the rack. Thecooling unit 16 can further be configured as one, two or three modules.In the embodiment shown in FIG. 1, a three-module cooling unit is used.

In the embodiment of FIG. 1, each of row 32 and row 34 is comprised ofsix racks. In embodiments of the invention, the number of racks and thefunction of the equipment in the racks can vary. In one embodiment ofthe invention, the racks 18 are modified standard 19 inch racks, such asthose available from American Power Conversion Corporation of WestKingston, R.I., under the trade name NETSHELTER VX Enclosures®.

The back face of each of the power distribution unit 14, the powerprotection unit 12, the floor mounted cooling unit 16, and the equipmentracks 18 faces the interior of the modular data center 10, or the hotroom 22. Essentially, the back faces of the racks in row 32 face theback faces of the racks in row 34. In one embodiment, the equipmentracks 18 have their rear doors removed so that each rack 18 remains opento the inside of the hot room 22. In the embodiment shown, the modulardata center 10 contains seven equipment racks 18. Alternatively, inanother embodiment, six equipment racks 18 complete the rows, but morethan seven equipment racks 18 can complete the rows contained in thedata center 10 and can be adjacent to one another or adjacent to otherenclosures in the data center 10, such as the power distribution unit14, the power protection unit 12, or the floor mounted cooling unit 16.

The door 52 located at the end of the row of racks is attached withhinges 53 to a detachable frame 55. The detachable frame 55 is locatedbehind the power protection unit 12. The detachable frame may bepositioned behind any one of the power protection unit 12, the powerdistribution unit 14, or the equipments racks 18, depending on which ofthe units are positioned at the end of a row in the data center 10. Thedetachable frame 55 allows the door 52 to be quickly removed forreplacement of the power protection unit 12 if necessary. The hot roomis accessible by the door 52 and can be monitored through theobservation window 54. Preferably, a door 52 is located at each end ofthe hot room 22. Generally, the door 52 is a 2×36 inch insulated,lockable steel door having an insulated observation window 54.

The cold water supply and return 60 can enter the hot room throughsupply pipes into the roof 56 or directly into the roofs of the racks.The voltage feed 58 can also enter through the roof 56 or through theroofs of the racks. Alternatively, the cold water supply and return 60and the voltage feed 58 enter the hot room through a raised floor onwhich the modular data center rests or from another location outside ofthe room and into the racks, such as into the sides of the racks.

The roof panel 56 is preferably a semi-transparent plexiglass roof panelsupported by steel supports 62 that are positioned at intervals alongthe length 72 of the data center 10. The roof 56 extends to cover thetop of the hot room 22 located in the middle of the rows of racks. Theroof 56 can be easily detachable to allow for removal of racks 18 or thepower protection unit 12 when necessary. A roof panel 56 constructed ofsemi-transparent plexiglass allows room light to enter the spacedefining the hot room 22. Additionally, the plexiglass roof 56 ispreferably substantially airtight.

The hot room 22 is completely enclosed and has walls formed by thebackside of the racks 18 and walls comprised of the door 52 attached ateach end of the hot room 22. Alternatively, panels without doors can bethe walls that complete the hot room. The hot room 22 is a substantiallyairtight passageway when the roof panel 56 is in place. Thus, themodular data center 10 is an enclosed computer infrastructure defined onits outside perimeter by the front face of each of the racks 18, powerprotection unit 12, power distribution unit 14, and cooling unit 16, andhaving a hot room 22 in its midsection. The outside walls of the hotroom formed by the doors 52 are a portion of two of the outside walls ofthe modular data center 10.

Referring to FIG. 2, a top view of a modular data center 10 in oneembodiment of the invention is shown. The modular data center of FIG. 2is similar to that of FIG. 1, but has five racks in each of row 32 androw 34, rather than the six racks in each row of FIG. 1. With likenumbers referring to like embodiments, the modular data center 10 ofFIG. 2 is comprised of the power distribution unit 14, the powerprotection unit 12, the floor mounted cooling unit 16, the equipmentracks 18, and the hot room 22. The power protection unit 12 ispositioned directly adjacent to one side of the power distribution unit14, while a floor-mounted cooling unit 16 is positioned on the otherside of the power distribution unit. A service clearance area 20surrounds the modular data center 10. In FIG. 2, an embodiment of theinvention is shown having six equipment racks 18 and a cooling unit 16having two modules.

The dimensions of the modular data center 10 depend on the number ofracks included in each of the rows of racks. For example, and referringagain to FIG. 1, a data center 10 having six equipment racks 18 can havea width of 120″, indicated by arrow 28, a length of 120″, indicated byarrow 29, and a height of 36″, indicated by arrow 24. The height 24 ofthe data center can be 36″, while the service clearance is preferably36″ in width 26. With the inclusion of the service clearance 20, thefloor surface area for the data center 10 is, preferably, a length 30 of192″ and a width 30 of 192″. Alternatively, and referring to FIG. 2, adata center 10 having seven equipment racks 18 can have a width of 120″and a length of 144″, while the height of the data center 10 is 36″.With the inclusion of the service clearance 20, the floor surface areafor an alternate data center is 192″ by 216″. The dimensions of themodular data center are given only as examples, but can varysignificantly depending upon the type and size of racks used to designthe data center.

The modular data center 10 is operational when provided with a source ofchilled water 60 and a voltage feed 58. The data center can include anumber of different power input designs, but is preferably a 40 kWdesign, allowing 6.7 kW/rack in a system having six equipment racks 18,or 5.7 kW/rack in a system having seven equipment racks 18, for example.Cold water enters the floor mounted cooling units 16 via supply lines60. A common supply line 60 can provide cold water to one or morecooling units simultaneously, as the cooling units 16 are connected tothe common supply 60 with flexible hose that is easily disconnected.

The modular data center 10 provides cooling for equipment in the datacenter as follows. Air from the room, or ambient air, filters throughthe front of the racks 18 to cool the equipment stored in the racks 18.Air enters through the front of the racks 18 and is expelled out of thebackside of the racks 18. As the air passes through the equipment racks18, the temperature of the air rises. The respectively warmer air isexpelled into the hot room 22. The hot room 22 contains the warm air andprevents the warm air from mixing with air in the surrounding room. Thecooling unit 16 draws warm air from the hot room and return cool air tothe room outside the data center 10. The warm air enters the coolingunits 16 directly from the hot room 22. The cold water supply 60 actswithin the cooling unit to lower the temperature of the air, and thecooled air is then released into the surrounding area. The air isrecycled to the surrounding room at a substantially cooled temperature.For example, the cooling unit 16 generally receives air from the hotroom at 95° F. and cools it to a temperature of approximately 72° F.before it is released into the area surrounding the data center 10. Thefloor mounted cooling unit 16 operates at substantially higher supplyand return temperatures, allowing realization of high capacity withoutlatent heat removal.

Referring to FIG. 3, with further reference to FIGS. 1–2, the datacenter 10 is configured to perform a process of cooling equipment storedin enclosed racks using an infrastructure having independent power andcoolant supplies. The process 100 includes the stages shown, althoughthe process 100 may be altered, e.g., by having stages added, deleted,or moved relative to the stages shown.

The process 100 of FIG. 3 includes stage 102, wherein power is suppliedfrom a power distribution unit to a plurality of equipment racks 18. Theequipment racks 18 may contain a variety of electronic equipment thatrequires a consistent power supply to avoid system downtime. A voltagefeed 58 is connected to the power distribution unit 14, and a powerprotection unit 12 is installed adjacent to the power distribution unit14 to ensure redundant power supply.

At stage 104, the racks 18 draw cool air from the surrounding roomthrough the front face of the racks 18. There may, for example, be anair distribution unit within the racks and/or within equipment containedin the racks that draws the room air into the rack 18 and distributesthe air throughout the rack to cool components contained in the rack. Asthe air passes through the rack 18, the air increases in temperature.

At stage 106, the racks 18 expel the air at an increased temperatureinto the hot room 22. The air is expelled out of the backside of theracks 18. As described above, in one embodiment, the racks 18 do nothave rear doors. In other embodiments, rear doors may be included on theracks with the warm air being expelled into the hot room through ventsin the doors. Air is held in the hot room 22 at an increased temperatureand mixing of the warm air with the surrounding ambient air isprevented.

At stage 108, the cooling unit draws the warm air from the hot room 22.The cooling unit 16 uses the cold water from the cold water supply 60 tocool the air from the hot room. At stage 110, the cooled air is releasedfrom the cooling unit into the surrounding room, which completes thecooling cycle. The air in the surrounding room is then drawn into theracks 18 once again, and the cycle continues.

Other embodiments are within the scope and spirit of the appendedclaims. For example, air could be forced up through the equipment racks18. Air moved through the racks 18 could be of varying temperatures,including hot air. The data center 10 may be configured to distributegases other than air. Additionally, a refrigerant or other coolant maybe used rather than cold water. Further, a controller can be coupled tothe data center 10 to monitor air temperatures and flow rates, as wellas power supply so that each rack is provided adequate powerconsistently. A data center may contain a single equipment rack 18having a single cooling unit 16 creating an individual data center,whereby power is distributed to a single data center 10 or multiplesingle-rack data centers simultaneously.

Further, in embodiments of the present invention, the roof over the hotarea may include a number of fans that are controlled to exhaust airfrom the hot area in the event of a failure of an air conditioning unitin the modular data center, and/or when air temperature in the hot areaexceeds a predetermined limit.

Having thus described at least one illustrative embodiment of theinvention, various alterations, modifications and improvements willreadily occur to those skilled in the art. Such alterations,modifications and improvements are intended to be within the scope andspirit of the invention. Accordingly, the foregoing description is byway of example only and is not intended as limiting. The invention'slimit is defined only in the following claims and the equivalentsthereto.

1. A modular data center comprising: a plurality of racks, each of theracks having a front face and a back face, wherein the racks arearranged in a first row and a second row such that the back faces of theracks of the first row face the back faces of the racks of the secondrow and wherein the racks are configured to accept air through the frontfaces of the racks and expel the air through the back faces of theracks; a cooling unit positioned in one of the first row and the secondrow, the cooling unit configured to draw air through a back face of thecooling unit and deliver cooled air through a front face of the coolingunit to the front faces of the plurality of racks; an enclosure tocollect air expelled from the plurality of racks, wherein the first rowand the second row comprise a portion of the enclosure that collects theexpelled air.
 2. The modular data center of claim 1, wherein theenclosure further comprises: a first end panel coupled between a firstrack of the first row and a first rack of the second row, the first endpanel having a bottom edge and a top edge; a second end panel coupledbetween a second rack of the first row and a second rack of the secondrow, the second end panel having a bottom edge and a top edge; and aroof panel coupled between the top edge of the first end panel and thetop edge of the second end panel.
 3. The modular data center of claim 2,wherein the cooling unit draws air from the enclosure that collects theexpelled air, cools the air and delivers cooled air out of the frontface of the cooling unit.
 4. The modular data center of claim 2, whereinat least one of the first end panel and the second end panel includes adoor.
 5. The modular data center of claim 2, wherein at least a portionof the roof panel is translucent.
 6. The modular data center of claim 1,wherein at least one of the racks includes an uninterruptible powersupply to provide uninterrupted power to equipment in at least one otherrack of the plurality of racks.
 7. The modular data center of claim 1,wherein the first row is substantially parallel to the second row.
 8. Asystem for restricting mixing of air in a data center having a pluralityof racks, each of the racks having a front face and a back face, whereinthe racks are arranged in a first row and a second row such that theback faces of the racks of the first row face the back faces of theracks of the second row, the system comprising: a cooling unit todeliver air to the front faces of the plurality of racks; and anenclosure for collecting air released from the back faces of theplurality of racks, the enclosure configured to substantially containthe air in an area between the first row and the second row and having aroof panel coupled to the first row of racks and the second row of racksconfigured to span a distance between the first row of racks and thesecond row of racks.
 9. The system of claim 8 wherein the enclosurefurther comprises a first end panel coupled between a first rack of thefirst row and a first rack of the second row and a second end panelcoupled between a second rack of the first row and a second rack of thesecond row.
 10. The system of claim 9 wherein at least one of the firstend panel and the second end panel includes a door.
 11. The system ofclaim 8 wherein at least a portion of the roof panel is translucent. 12.The system of claim 8 wherein at least one of the plurality of racksincludes an uninterruptible power supply to provide uninterrupted powerto equipment in at least one other rack of the plurality of racks. 13.The system of claim 8 wherein the air collected in the enclosurecomprises the supply air for the cooling unit to deliver to the frontfaces of the plurality of racks.